Abstract : Temperature profiles obtained by Differential Inversion (DI) applied to SSM/T data have unacceptably large deviations from co-located radiosonde observations. These deviations arise due to the small number of available SSM/T channels and from the requirement for well determined surface emissivities, which have not been available heretofore. Recent results by Felde and Pickle on surface emissivity determination using SSM/I data suggest the possibility of using those surface emissivity determinations as part of the data input to DI. Such a multispectral approach to DI would retain DI's advantages of computational efficiency and direct connections to the physical content of the equation of radiative transfer.